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Fishery and Sea ResourcesYear S1 S2 B1 B21998 0.14 0.14 13,003.63 12,982.651999 0.21 0.16 2,404 3,231.492001 0.39 0.27 4,650.07 6,711.432005 0.34 0.22 8,200.96 12,729.202006 0.30 0.20 5,897.96 9035.79Table 3: Values of Spawning fraction and Biomass calculated by new (S1 and B1) andold (S2 and B2) methods.Figure 4: Variations of Spawning Fraction between new (S1) and old (S2) evaluationmethods.spawning it is almost impossible to find thefirst age class POF. In 2005 the catches startat 07:30 a.m. and the POFs 0 disappear at6:00 a.m. about.4 DiscussionThe importance of DEPM application tosuitable management of commerciallyimportant fish resource, as sardines andanchovy, is confirmed worldwide since1980s. Knowledge of species reproductivebiology and a survey design adaptedto local population dynamics are requiredto optimize DEPM performance in termsof bias, precision and cost. The methodseems better adapted to the life historyof anchovies than of sardines, leading tomore precise estimates of anchovy spawningbiomass and facilitating extensions ofthe method to estimate total biomass [14].Spawning fraction (S) is the proportion ofmature females in the target population thatspawn daily, and often constitutes the mostdifficult adult DEPM parameter to estimate[15]. Detailed knowledge of the reproductivebiology of the species may allowto obtain much more accurate estimations.Several studies revealed the ephemeral lifeof POFs, lasting usually between 15 to 722120